THE MOLECULAR BASIS OF INHERITANCE
DNA REPLICATION
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
mRNA
|
|
|
tRNA
|
|
|
rRNA
|
|
|
DNA
|
Detailed explanation-1: -As we saw briefly in the introduction, molecules called transfer RNAs (tRNAs) bring amino acids to the ribosome.
Detailed explanation-2: -transfer RNA (tRNA), small molecule in cells that carries amino acids to organelles called ribosomes, where they are linked into proteins. In addition to tRNA there are two other major types of RNA: messenger RNA (mRNA) and ribosomal RNA (rRNA).
Detailed explanation-3: -During protein synthesis, tRNAs with attached amino acids are delivered to the ribosome by proteins called elongation factors, which aid in association of the tRNA with the ribosome, synthesis of the new polypeptide, and translocation (movement) of the ribosome along the mRNA.
Detailed explanation-4: -The tRNA carries the amino acid that corresponds to that codon. The next mRNA codon is now exposed in the ribosome’s other docking site. A tRNA with the complementary anticodon is attracted to the ribosome and binds to this codon. The tRNA carries the next amino acid in the polypeptide chain.
Detailed explanation-5: -It does this by matching each set of three nucleotides (codon) in mRNA with the complementary tRNA anticodon. The complementary tRNA enters via the A site on the ribosome. The amino acid carried by that tRNA is then bonded to the protein chain growing in the P site of the ribosome.